(a) Field of the Invention
This invention relates to a joint structure between members for joining two members together.
(b) Description of the Related Art
As an example of known joint structures for joining two members together, U.S. Pat. No. 6,206,604 (hereinafter, referred to as Patent Document 1) discloses a joint structure between members in which a first member formed to cover a vehicle engine from above is joined to the engine. In the disclosed joint structure, the first member is releasably joined to a second member fixed to the top of the engine and formed in an upwardly extending column. A rubber elastic member is interposed between the first and second members. The elastic member reduces engine vibrations transmitted to the first member.
The elastic member has a cylindrical shape the central axis of which runs vertically, and is accommodated and held in an annular frame formed on the bottom surface of the first member. A tapered hole is formed in the bottom surface of the elastic member to receive a spherical part formed at the top end of the second member. The elastic member has a holding part formed just above the tapered hole. The holding part fits on and holds the spherical part of the second member inserted therein through the tapered hole. The holding part is contiguous with the tapered hole.
The holding part of the elastic member in Patent Document 1 is formed in a substantially spherical shape to cover the spherical part of the second member from its top end to the vicinity of its bottom end. The holding part formed in a substantially spherical shape provides the following effects. First, even if a force is applied which tends to further move the second member relative to the first member in the direction of insertion of the second member with the spherical part of the second member held in the holding part, the top end of the second member is lodged on the top end portion of the holding part to restrain further movement of the second member in the direction of insertion. Second, even if a force is applied which tends to move the second member in the direction of extraction from the elastic member, the lower portion of the spherical part of the second member is lodged in the lower portion of the holding part to prevent easy extraction of the second member. In this manner, the first member can be held in a fixed position.
In molding an elastic member of cylindrical shape having a hole open at its end surface as in Patent Document 1, use is generally made of a mold that is joined and separated in the direction of a central axis of the elastic member.